The Kindergarten Rule of Sustainable Growth

The relationship between economic growth and the environment is not well understood: we have only limited understanding of the basic science involved and very limited data. Because of these difficulties it is especially important to develop a series of relatively simple theoretical models that generate stark predictions. This paper presents one such model where societies implement the Kindergarten rule of sustainable growth.' Following the Kindergarten rule means implementing zero emission technologies in either finite time or asymptotically. The underlying simplicity of the model allows us to provide new predictions linking the path of environmental quality to pollutant characteristics (stocks vs. flows; toxics vs. irritants) and primitives of the economic system. It also provides a novel Environmental Catch-up Hypothesis.

A microrod-resonator Brillouin laser with 240 Hz absolute linewidth

We demonstrate an ultralow-noise microrod-resonator based laser that oscillates on the gain supplied by the stimulated Brillouin scattering optical nonlinearity. Microresonator Brillouin lasers are known to offer an outstanding frequency noise floor, which is limited by fundamental thermal fluctuations. Here, we show experimental evidence that thermal effects also dominate the close-to-carrier frequency fluctuations. The 6-mm diameter microrod resonator used in our experiments has a large optical mode area of ~100 {\mu}m$^2$, and hence its 10 ms thermal time constant filters the close-to-carrier optical frequency noise. The result is an absolute laser linewidth of 240 Hz with a corresponding white-frequency noise floor of 0.1 Hz$^2$/Hz. We explain the steady-state performance of this laser by measurements of its operation state and of its mode detuning and lineshape. Our results highlight a mechanism for noise that is common to many microresonator devices due to the inherent coupling between intracavity power and mode frequency. We demonstrate the ability to reduce this noise through a feedback loop that stabilizes the intracavity power.Comment: 11 pages, 5 figure

Bulletin No. 25: Salt Marsh Plants of Connecticut

32 pp. 1980. Illustrated guide to 22 plants which grow in our tidal wetlands

Mathematical circulatory system model

A system and method of modeling a circulatory system including a regulatory mechanism parameter. In one embodiment, a regulatory mechanism parameter in a lumped parameter model is represented as a logistic function. In another embodiment, the circulatory system model includes a compliant vessel, the model having a parameter representing a change in pressure due to contraction of smooth muscles of a wall of the vessel

Automated Laser Scatter Detection of Near-Surface Defects and Machining Damage in Ceramic Components

The need to achieve higher gas firing temperatures in new stationary gas turbines has led to the requirement for stronger, longer-lasting materials capable of functioning in environments more severe than traditional materials permit. The higher operating temperatures seen in these environments (\u3e1300 °C) would substantially increase energy efficiency and reduce emissions. Because conventional materials are not suitable, alternate materials are being considered for turbine components. Included among these are the Si3N4 ceramics. In an effort to improve and extend the working lifetime of the components, improvement in the detection of critical defects (such as cracks, voids, inclusions, or microstructural variations) in their surface and near-subsurface regions is being investigated. Although all of the defects can occur either during manufacturing or in operation, the specific type of defect most likely to occur in a given component depends on a various factors, including the material system, processing and machining parameters, component geometry, and application environment

Amiodarone in Pediatric Patients

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75189/1/j.1540-8167.1986.tb01730.x.pd